Tire retreading is a process by which used tires receive a new tread to extend their service life. Since the useful life span of most tires goes far beyond that of their tread component, reusing old tire casings for retreading is both cost effective and environmentally friendly. Generally, retreading involves removing the old worn out tread from the tire casing and bonding a new tread onto the cleaned tire by a process of vulcanization.
New tread for precured retreading applications is typically molded as a single piece with the tread pattern on one side. The opposing side is later prepared to bond to the tire. During the molding and curing process a hard, shiny and smooth oxide layer forms on the tread. To prepare the tread to bond to the tire this layer must be removed. The removal of this layer is typically done with buffing of the tread using several stages of expendable wire brushes in an energy intensive process. The tread buffing process is not only energy intensive but also labor intensive. Once the oxidation layer is buffed off the precured tread, the new tread is cemented in order to prevent future oxidation. The cement is then covered with gray polyfilm for ultraviolet light protection, and the tread is rolled up and covered with stretch wrap to protect it from moisture, dirt, and containments. Since tread is typically sold by unit weight, cementing, adding polyfilm, and stretch wrapping the new tread increases its cost.